Skylights placed on sloped roofs have a tendency to be leak-prone. Further, the costs are high when it becomes necessary to alter the roof sheets to accommodate the skylights, and there is an ongoing need to address loads imposed by heavy snow loads or personnel. These problems are exacerbated as the skylights increase in size and comprise a large portion of the roof.
Skylights are composed typically of four metal curbs around its perimeter. The curbs are typically made of sheet steel in the range of 14 gage thickness or aluminum in the range of 0.125″ thickness and are insulated by fiberglass batts or isocyanurate blocks. The longitudinal skylight curbs are made in sections which are screwed or bolted together so as to make long vertical curbs. The width-wise distance between curbs is specifically set so that metal roof panels which comprise the main roof will allow the skylight curbs to occupy the area which would have been occupied by one or two or three metal roof sheets. By making these curbs to a specified width, the roof sheets immediately below the skylight can be assembled in the normal fashion and will join each other in their normal seaming method. Typically, the skylights are placed with one end at the ridge of the building, thereby eliminating the need for crickets or saddles. Backseams formed by crickets or saddles have been one source of leakage in many skylights in the past.
Seams and the resulting leakage have been a source of problems for skylight systems. As the size of the skylight increases so too must the framing and thus the number of joints and scams, especially within standing seam roofs which comprise upright legs and thus form even more seams at the skylight framing. The rooting industry seldom uses skylights within standing seam roofs, mainly because the standing scams direct water flow downward resulting in water being directed into the frame. Because of this, skylights in the past have typically been installed as a large number of small units. However, it is difficult to put “crickets” in a standing seam roof because you are required to navigate around the standing scams. If the standing seams are cut in the process it may weaken the structural strength of the panel.
There is a need then for a skylight system which maintains the aesthetics of being wide and narrow so as to occupy a large-area as a single panel but which eliminates the potential for leakage, especially within sloped, standing seam roots.